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Data Integrity in Dataset Merges
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Data Integrity in Dataset Merges

MediumSQL · PostgreSQL

Problem

How do you ensure data integrity when merging datasets from different sources?

Using the provided student datasets, write a SQL query that compares records by student_id, preserves values from both sources, and classifies each record based on whether the data is consistent, conflicting, or present in only one source.

Output

  1. One row per student ID found in either source.
  2. Include both sources' name, email, and program values, plus integrity_status.
  3. Order by student_id ascending.

Schema

source_a_students
ColumnTypeDescription
student_idPKINTStudent identifier from source A
full_nameVARCHAR(150)Student full name from source A
emailVARCHAR(255)Student email address from source A
programVARCHAR(120)Academic program from source A
source_b_students
ColumnTypeDescription
student_idPKINTStudent identifier from source B
full_nameVARCHAR(150)Student full name from source B
emailVARCHAR(255)Student email address from source B
programVARCHAR(120)Academic program from source B
Tablessource_a_studentssource_b_students
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